Describe the Lerp node (#246)

Behaviors lists Lerp with its eases. Development counts 1459 checks.

Behaviors.md

@@ -131,7 +131,10 @@ playing use the same two words.
   `On timer` (fires on the first frame past each due time; `late` says by how much, so `time - late` is exactly a multiple of the interval), `On collision enter/stay/exit` (stay every frame, or with an interval; while playing enter and stay tell normal, impulse and point of the contact), `On click` (the mouse pressed on the owner — anywhere when it has none), `On animation finished`, `On state entered`, `On state exited` (one output per state, see *State machines*), `Start` · flow `Branch`, `Sequence`, `Repeat`, `Run behavior`, `End`, and the four that move or follow a state machine, `State branch`, `Set state`, `Set state by name`, `State transition` (see *State machines*) · data `Self`, `Owner`, `Parent`, `Object by name`, `Child by name` (the nearest object of that name below the given one: its children, then their children, and so on; within a level the first in hierarchy order, nothing when none is called so), `Name of`,
   `Is asset` (is this object an instance of asset X — how you tell what you collided with),
   `Variables`, `Properties` (every property row of the target's type, the transform rows `scale`, `rotation`, `mirrorX`, `mirrorY` included — how a graph turns a sprite), `Get position` (local and world), `Is enabled`, literals `Number`/`Text`/`Boolean`/`Texture`/`State machine`/`Sound`/`Scene`/`Animation`/`Asset`, `Add/Subtract/Multiply/Divide`,
-  `Min/Max/Abs/Sqrt/Clamp`, `Floor/Ceil/Round`, `Modulo`, `Random`, `Time`, `To text`, `To number`, `Join text`,
+  `Min/Max/Abs/Sqrt/Clamp`, `Lerp` (from a to b as t runs from 0 to 1, t held in 0…1; the setting
+  *Ease* bends the way: *Linear*, *In* starts slow, *Out* ends slow, *In-out* both, all quadratic —
+  one node where a slide or a flight used to take a Subtract, a Multiply and an Add per axis),
+  `Floor/Ceil/Round`, `Modulo`, `Random`, `Time`, `To text`, `To number`, `Join text`,
   `Substring`, `Find text`, `Equals`, `First not empty` (a, unless a is empty, then b; the setting
   *Empty means* says how much counts as empty: *Any empty value* is nothing, 0, "", false, an empty
   list, or a struct whose fields are all empty such as a position (0, 0), so a real 0 or false on a

Development.md

@@ -15,7 +15,7 @@ npm run build        # writes dist/ and regenerates index.html
 php tools/make-user.php <name> <password> [admin|user]        # an account; every tool signs in (see Accounts)
 php tests/php/accounts.test.php                               # the API's account rules, no server needed (CI's gate job)
 php tests/php/snapshots.test.php                              # the snapshot store (#231), the same way
-node tools/seed-e2e.mjs && node tools/e2e.mjs                 # 1457 editor checks, screenshots in /tmp/gm-e2e-*.png
+node tools/seed-e2e.mjs && node tools/e2e.mjs                 # 1459 editor checks, screenshots in /tmp/gm-e2e-*.png
 GM_STEPS=20 node tools/e2e.mjs                                # or 1-12, or 6,20 — a subset while working on one step
 ./e2e.sh start [GM_STEPS]                                     # the same run detached, see below
 ./e2e.sh status                                               # live progress, or the last run's result